Since its launch on July 23, 1999, the Chandra X-ray Observatory has been NASA's flagship mission for X-ray astronomy, taking its place in the fleet of "Great Observatories."

ESO is the pre-eminent intergovernmental science and technology organization in astronomy. It carries out an ambitious program focused on the design, construction and operation of powerful ground-based observing facilities for astronomy to enable important scientific discoveries.

GALEX’s observations are telling scientists how galaxies, the basic structures of our Universe, evolve and change. Additionally, GALEX observations are investigating the causes of star formation during a period when most of the stars and elements we see today had their origins.

The Gemini Observatory consists of twin 8-meter optical/infrared telescopes located on two of the best sites on our planet for observing the universe. Together these telescopes can access the entire sky.

Herschel will investigate the history of how stars and galaxies formed and to study how they continue to form in our own and other galaxies. Herschel will observe at wavelengths never covered before.

The Hubble Space Telescope is a collaboration between ESA and NASA. It's a long-term, space-based observatory. The observations are carried out in visible, infrared and ultraviolet light. In many ways Hubble has revolutionized modern astronomy, by not only being an efficient tool for making new discoveries, but also by driving astronomical research in general.

Consisting of a 0.85-meter telescope and three cryogenically-cooled science instruments, Spitzer is the largest infrared telescope ever launched into space. Its highly sensitive instruments give us a unique view of the Universe and allow us to peer into regions of space which are hidden from optical telescopes.